[PATCH installer 13/15] tui: views: add widget for displaying a group of checkboxes

[Christoph Heiss <c.heiss@proxmox.com>]

Adds a simple view which displays multiple checkboxes, each optionally
associated with some user-defined data.

Signed-off-by: Christoph Heiss <c.heiss@proxmox.com>
---
 proxmox-tui-installer/src/views/mod.rs | 106 ++++++++++++++++++++++++-
 1 file changed, 105 insertions(+), 1 deletion(-)

diff --git a/proxmox-tui-installer/src/views/mod.rs b/proxmox-tui-installer/src/views/mod.rs
index a343e60..b4896e2 100644
--- a/proxmox-tui-installer/src/views/mod.rs
+++ b/proxmox-tui-installer/src/views/mod.rs
@@ -5,7 +5,9 @@ use cursive::{
     event::{Event, EventResult},
     theme::BaseColor,
     view::{Resizable, ViewWrapper},
-    views::{EditView, LinearLayout, NamedView, ResizedView, SelectView, TextView},
+    views::{
+        Checkbox, DummyView, EditView, LinearLayout, NamedView, ResizedView, SelectView, TextView,
+    },
 };
 
 mod bootdisk;
@@ -626,3 +628,105 @@ impl CidrAddressEditView {
 impl ViewWrapper for CidrAddressEditView {
     cursive::wrap_impl!(self.view: LinearLayout);
 }
+
+/// List of checkboxes, each with an associated label and optional user-defined
+/// data for identifying its meaning.
+pub struct CheckboxGroup<UDT = ()> {
+    view: LinearLayout,
+    user_data: HashMap<usize, UDT>,
+}
+
+impl<UDT> CheckboxGroup<UDT> {
+    pub fn new() -> Self {
+        Self {
+            view: LinearLayout::vertical(),
+            user_data: HashMap::new(),
+        }
+    }
+
+    pub fn add(&mut self, label: &str, checked: bool, data: UDT) {
+        self.user_data.insert(self.view.len(), data);
+        self.view.add_child(
+            LinearLayout::horizontal()
+                .child(Checkbox::new().with_checked(checked))
+                .child(DummyView)
+                .child(TextView::new(label)),
+        );
+    }
+
+    pub fn entries(&self) -> impl Iterator<Item = (bool, &UDT)> {
+        CheckboxGroupIterator {
+            group: self,
+            index: 0,
+        }
+    }
+
+    pub fn set_enabled(&mut self, enabled: bool) {
+        for i in 0..self.view.len() {
+            if let Some(checkbox) = self
+                .view
+                .get_child_mut(i)
+                .and_then(|v| v.downcast_mut::<LinearLayout>())
+                .and_then(|v| v.get_child_mut(0))
+                .and_then(|v| v.downcast_mut::<Checkbox>())
+            {
+                checkbox.set_enabled(enabled);
+            }
+        }
+    }
+
+    pub fn update_labels(&mut self, callback: &dyn Fn(bool, &mut TextView, &mut UDT)) {
+        for i in 0..self.view.len() {
+            if let Some(inner) = self
+                .view
+                .get_child_mut(i)
+                .and_then(|v| v.downcast_mut::<LinearLayout>())
+            {
+                let checked = inner
+                    .get_child(0)
+                    .and_then(|v| v.downcast_ref::<Checkbox>())
+                    .map(|v| v.is_checked())
+                    .unwrap_or(false);
+
+                let label = inner
+                    .get_child_mut(2)
+                    .and_then(|v| v.downcast_mut::<TextView>());
+
+                let data = self.user_data.get_mut(&i);
+
+                if let (Some(label), Some(data)) = (label, data) {
+                    callback(checked, label, data);
+                }
+            }
+        }
+    }
+}
+
+impl<UDT: Send + Sync + 'static> ViewWrapper for CheckboxGroup<UDT> {
+    cursive::wrap_impl!(self.view: LinearLayout);
+}
+
+pub struct CheckboxGroupIterator<'a, UDT> {
+    group: &'a CheckboxGroup<UDT>,
+    index: usize,
+}
+
+impl<'a, UDT> Iterator for CheckboxGroupIterator<'a, UDT> {
+    type Item = (bool, &'a UDT);
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let checked = self
+            .group
+            .view
+            .get_child(self.index)?
+            .downcast_ref::<LinearLayout>()?
+            .get_child(0)?
+            .downcast_ref::<Checkbox>()?
+            .is_checked();
+
+        let data = self.group.user_data.get(&self.index)?;
+
+        self.index += 1;
+        Some((checked, data))
+    }
+}
-- 
2.55.0